Auto body and frame straightening devices

ABSTRACT

Apparatus is provided to apply pulling forces from any direction from any elevation around a vehicle being repaired and/or serviced. The apparatus is arranged so personnel using it are concerned with minimal physical lifting movements and minimal setup arrangements of the apparatus. Each embodiment of the apparatus utilizes at least one tower assembly equipped with an elongating subassembly to move a tension member, through directional change devices, as it remains secured to some portion of a vehicle, thereby undergoing at least one repositioning pull in a direction opposite to at least one prior force that previously caused some of the damage and/or misalignment. Depending on the magnitude of the restoring force required, the tower, other towers, and/or other structures may be secured together and/or to the vehicle as well, to create a firm basis for anchoring the apparatus and/or the vehicle as one or more reactive forces are controllably created. Depending on the anticipated use of the apparatus and the capital expenditures to be made, the apparatus is made available in different embodiments, ranging from a sole location of a tower to multiple locations of several towers related to overall reactive structures and/or vehicle ramps serving as mutual multiple holding or anchoring places of forces applied to the vehicle, as the elongating subassemblies of the towers are moved to create the restorative pulling forces.

United States Patent 1 Chisum l l AUTO BODY AND FRAME STRAIGHTENINGDEVICES Finis L. Chisum, ll l3 W. l6th. Claremore, Okla, 74107 [76]Inventor:

[63] Continuationin-part of Ser. No. 810,940. March 27,

I969. Pat. No. 3.630.066.

[52] U.S. Cl 72/305; 72/705 [51] int. Cl 821d H12 [58] Field of Search72/705. 305. 306. 457

[56] References Cited UNITED STATES PATENTS 2,563,527 8/[95] Gingrich etal. 72/705 2.674.293 4/1954 Elam 72/705 2.705040 3/]955 Howick....72/705 2.792.046 5/l957 Fagan 72/705 3.088.5l3 5/l963 MarquardL. 72/7053.340.720 9/l967 Chartier 72/705 3,5 l 8.867 7/1970 Rouis 72/7053.581.547 6/1971 Estigarribia 72/705 3.626.747 l2/l97l Rouis 72/7053.630.066 l2/l97l Chisum 72/705 3.729.978 5/1973 Lunardini 72/705Primary Exumine'rC. W. Lanham Assistanl E.raminerM. J. Keenan June 10,1975 [57} ABSTRACT Apparatus is provided to apply pulling forces fromany direction from any elevation around a vehicle being repaired and/orserviced. The apparatus is arranged so personnel using it are concernedwith minimal physical lifting movements and minimal setup arrangementsof the apparatus. Each embodiment of the apparatus utilizes at least onetower assembly equipped with an elongating subassembly to move a tensionmember, through directional change devices. as it remains secured tosome portion of a vehicle, thereby undergoing at least one repositioningpull in a direction opposite to at least one prior force that previouslycaused some of the damage and/or misalignment. Depending on themagnitude of the restoring force required, the tower, other towers.and/or other structures may be secured together and/or to the vehicle aswell. to create a firm basis for anchoring the apparatus and/or thevehicle as one or more reactive forces are controllably created.Depending on the anticipated use of the apparatus and the capitalexpenditures to be made. the apparatus is made available in differentembodiments. ranging from a sole location of a tower to multiplelocations of several towers related to overall reactive structuresand/or vehicle ramps serving as mutual multiple holding or anchoringplaces of forces applied to the vehicle, as the elongating subassembliesof the towers are moved to create the restorative pulling forces.

36 Claims, 32 Drawing Figures SHEET PMENTEDJUN 10 ms Rik m s wm mv wv D(me/17,,

. QQN

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PATENWUJUN 10 1915 M11 1 an 1 3w Maw IN 0 Rm 0 0.3m mum 0 M 0 av O 0 1|H 0 O M l l! h N\ Qfix 3w M E mww EN EN 1W1 SHEET PATENTEDJUHIO 19753.888100 SHEET 7 AUTO BODY AND FRAME STRAIGHTENING DEVICES CROSSREFERENCE TO RELATED APPLICATION This application is acontinuation-in-part of my copending application Ser. No. 8l0,940 filed:Mar. 27, 1969, now US. Pat. No. 3,630,066. This application furtherincludes subject matter divided from said copending application.

BACKG ROUN D OF INVENTION Present apparatus known to be available forcorrecting misalignment of vehicles and for returning frame and bodymembers of vehicles back to their predamage locations, as such servicesare performed by personnel in body shops and other service and repairshops, are not conveniently set up and operated to meet the demands ofpersonnel in various size repair shops. This invention is offered inmultiple embodiments to meet different requirements of cost, convenienceand service of many shops wherein personnel are seeking better apparatusto more economically perform their realignment and body repair services.

The apparatus known to be available prior to this invention. requiredpersonnel using it to make many lifts of heavy and/or awkward componentsunder awkward footing and overhead conditions during time consumingsetup periods. This was necessary to try to place components in variouswanted positions, many not being directly obtainable. where theresulting pulling forces would be applied most advantageously to restorevehicle frames and bodies to their originally designed positions. Whereprior attempts were made to obtain a greater range of pulling andanchoring locations, the resulting apparatus was often complex, large,costly, and inconvenient to manipulate, and moreover, often requiringspecial builiding configurations such as higher overhead space and/orfloor pits.

In contrast, this invention, in its various embodiments, to be selecteddepending on the anticipated volume of such repairs to be undertaken andthe capital funds available. is provided so personnel may convenientlyand quickly arrange the apparatus to pull on a vehicle frame and/or bodyin the most advantageous direction at one or more locations. As businessgrows, the offered embodiemtns are conveniently and economicallyincreased in capacity by acquiring components of other embodiments.Moreover at all times with respect to all personnel, straining,orvetiring and dangerous situations are avoided.

SUMMARY Apparatus for returning vehicle frame and fame components totheir original locations during repair and servicing of vehicles isprovided in various embodiments. each centering on the use of one ormore towers or pedestals including a length changing subassembly as thebasis of creating a restorative force applied in a selected direction toreturn one or more vehicle components to their original designedrelative location. the apparatus in all its embodiments: simplifies bodyand frame straightening operations; permits simple hookups for fastercorrection to damage at any point on a vehicle; reverses the damagesequencing of the wrecked car for a faster and more accurate body and-/or frame correction; allows more freedom for workmen who do not have tomove over or under any supporting beams or other structures; eliminatesheavy lifting by personnel; pulls in any desired angular direction; fitsin minimum amount of space; sets up in buildings with low ceilings;complies with equipment specifications presented by both small shop,medium and large shop operators; requires no pit but may be used inconjunction with one; needs no special surrounding building.

DRAWINGS OF PREFERRED EMBODIMENTS FIG. 1, including locationdesignations noted respectively as SUBSECTIONS A, B, C & D, is a sideelevation, with some portions broken away for illustrative purposes, ofa preferred embodiment of the apparatus being used to create restorativeforces applied to the vehicle shown;

FIG. 2, is a partial side elevation of the embodiment shown in FIG. Ipositioned to receive a vehicle which is electively either drivenforward on to the apparatus or backed on depending on where and how thevehicle is damaged;

FIG. 3. is a top plan view of the embodiment shown in FIG. 1,indicating, however, only the placement of the frame and some of thewheels of a vehicle;

FIGS. 3A, 3B, and 3C. indicate partially sectioned respective side, endand top views, of a body gripping clamp used particularly where onlybody portions and not heavier frame portions ar available to receive arestoring force;

FIG. 4, is a partial cross section view of the embodiment of FIG. Iindicating structure, arrangement, and operation of apparatus withrespect to one tower, its force creating accessorries and itsmultiposition attachment to other towers and their common attachedsupporting and servicing structures;

FIGS. 4A, 4B, and 4C, indicate partially sectioned views relatedspecifically to FIG. 4 and more repectively to: adjustable heightaccessories secured to a tower and used in determining the elevation ofa direct pulling force; some of the hydraulic accessories viewed atright angles with respect to their view in FIG. 4; and some of the crosssection structure of the radially positioned beam or arm structuresupporting the tower;

FIG. 5, is a view. primarily in section, taken along the lines 55 ofFIG. 3, indicating the raised position of the rail or ramp subassembliesand both their actuating accessories and safety brace accessories, asall appear when a vehicle is lifted into a horizontal position forundergoing repairs;

FIG. SA, is a partial sectional view related to FIG. 5, indicating how acontrol is located to operate hydraulic accessories used in raising therails or ramps near or at their ends that are conveniently lowered toreceive a vehicle and thereafter raised to position the vehiclehorizontally while repairs are undertaken.

FIG. 6, is a top view of another embodiment indicating how radiallypositioned towers are used with their respective rails or ramps whichare secured to building floors and/or to other tower and rampsubassemblies to provide many, but not all, of the operationaladvantages of the embodiment of FIG. 1;

FIGS. 7 and 8, partial top views, indicates how towers shown in FIG. 6used with their respective rails or ramps, which are movable orretractable casters, are conveniently positioned to apply restorativeforces;

FIG. 9 is a partial elevational view of the embodiment of FIG. 6, withsome portions removed, illustrating the semipermanent longitudinal floormounting of one tower and ramp or rail subassembly and a movablecross-positioned tower and ramp or rail subassembly;

FIG. is a partial elevational view, with most positions shown insection, indicating multiple radial positioning and securing of thetower shown in FIG. 6 with respect to its associated ramp or rail;

FIG. 11 is a plan view of how a tower shown in FIG. 6 with its castersupported ramp or rails is combined with wheel alignment ramp or railsto increase the capacity of such alignment apparatus by providing easilyadjustable restorative force equipment with it, making the resultingoverall apparatus very useful in accurately and quickly returning allportions of a vehicle frame to their original specified relativelocations;

FIG. 12 is a partial side elevational view of the combined tower, itsramp or rails, and alignment ramp or rails as shown in plan view in FIG.11, indicating how the tower is conveniently moved into position;

FIG. 13 is an elevational view, partially in section, indicating how aseparate tower or a pedestal may be removably and rotatably placed in aground or floor sleeve;

FIG. 14 is a plan view of a different embodiment of towers, equippedwith other adjustment components and guide rail riding accessories totravel about a track positioned where a vehicle is to be repaired; and

FIG. 15 is an elevational view, partially in section, indicating how anembodiment of FIG. 14 is specifically arranged with an overhead guiderail for moving the towers, where positioning rails or ramps aresupported in a pit structure to receive a damaged vehicle.

FIG. 16 is a plan view of a preferred embodiment of the treadways ofFIG. 3.

FIG. I7 is a cross sectional view taken along the line I7l7 of FIG. 16.

FIGS. l8, I9, 20, and 21 shown alternative construction for the treadwayof FIG. 16.

FIGS. 22A and 22B illustrate the type of holding device by means ofwhich a tension or compression force can be applied to the platformassembly.

FIGS. 23A and 23B are plan and elevation views respectively of a smallfastening device by means of which the embodiment of FIG. 22 can bepositioned at any height in the platform assembly.

DESCRIPTION OF PREFERRED EMBODIMENTS Introduction to all EmbodimentsThroughout all embodiments, the purpose is to pro vide apparatus that isquickly, safely and conveniently utilized to create one or morerestorative forces which create, in reverse, the forces originallycausing damage and/or misalignment. The embodiments of apparatus areoffered to meet the operational and economic speciftcations of allpersons so engaged in various sized shops as a part of the overallautomotive servicing industry.

In shops tht do a large volume of frame and body alignments and anoccasional front end alignment, the machine shown in FIGS. 1, 2, and 3is ideal. For shops that are limited for space, finances or both, thatdesire to have the convenience of their own frame equipment, the machineshown in FIG. 6 is very suitable. In shops of all sizes the portablemachine in FIGS. 7 and 12 is ideal for smaller alignment jobs that donot need to be placed on the heavier frame equipment. If shops do alarge volume of front-end alignments and an occasional frame and bodyalignment job, the machine in FIG. II is ideal. When the Unit 200 is notneeded on the frontend machine, it is ued as a portable frame and bodyalignment machine on smaller jobs that do not need to go on the rack.When one or more of these 200 units are united as shown in FIG. ll, youhave a complete body and frame alignment system, capable of handlingmajor frame and body alignment jobs. FIG. 14 shows another type ofmachine for large or specialized shops, utilizing the invention featuresfor greater economy and better tie-downs. In shops pushing for maximumvolumes, the tower subassembly shown in FIG. I3 is very handy. Thesepull towers are installed in strategic locations all over the shop, forquick and easy pulls when needed.

In respect to all these embodiments, most of the following objectivesare met: installation is made within a normal one stall area withoutaltering a building or without requiring any special wiring or plumbingbeyond a standard electrical plug and a compressed air outlet; a vehicleis tied down, pushed or pulled at any angle or height, with ample powerto bend any part of the vehicle without the use of heat or timeconsuming, back-breaking labor; all hookups are made, including manytie-down hookups, by an operator from a standing position, withoutlifting any heavy, awkward handling attachments or having to climb overor under any supporting beams; any good body man can operate theapparatus without receiving an extensive amount of instruction, theapparatus does not become a permanently fixed part of the building, onceit is installed; the apparatus does not require handling of heavy jacksor components; the apparatus is capable of pushing or pulling from onedirection or several directions at one time; the apparatus is designedto eliminate practically all physical strenuous lifting stooping andsquatting labor; operational capabilities of the apparatus is limitedonly by the operators imagination; the apparatus is capable of applyingpower from exactly the same angle of least resistance; the apparatus issimple enough to use throughout the range from a minor bumper alignmentjob to a major frame and body alignment job; the apparatus is used forfront end alignments; etc.

In reference to using the apparatus of most embodiments, proceduresfollowed are: position a vehicle on or near the apparatus oriented sothe maximum of damaged portions of the vehicle is adjacent the range ofmultiple positions of the towers and then tie or secure the vehicle tothe rails or ramps; move towers to the desired angular positions andsecure them to the rails or ramps; place hooks and/or clamps of therespective chains or other tensioning members to the damaged portions ofthe vehicle and position the elevation determining accessories to guidethese tensioning members as they are passed on to the respective tops ofthe towers for securing there or over and back down to a more convenientsecuring location; and operate the controls to elongate the towerscreating the restorative forces used in pulling out the damaged vehiclecomponents to their original or near original design relative locations.

Embodiment Shown in FIGS. 1 through 5, Elongatable Towers RadiallyAdjusted About a Pedestal to Inclinable Hold Down Ramps In FIG. I, avehicle or car is shown positioned on the apparatus or machine using aselected few hookups from among many that are available. Regardless ofwhere the damage is on the vehicle or in what direction the damageoccurred, it is possible to pull it back in line from the same angle thedamage occurred. By pulling at the damage from the same angle as thepoint of impact, the metals have much less resistance, permitting a muchfaster, more accurate alignment job, almost completely eliminating theuse of heat, for straightening of critical parts, avoiding changes inthe temper in metals causing weak spots or breakage.

The three pull towers 5 are adjustable to pull from any directiondesired. To move any tower, simply unscrew bolt l3 (See FIG. 4), pushtower around to the desired angle and reinstall bolt 13 and plate 14.Hook pull chain to damaged area and hookup is complete. With three pulltowers adjustable to pull at any height or angle, the frame and body ofthe damaged vehicle are all pulled back into alignment in the sameoperation, rather than pulling one and then the other, by pulling boththe frame and body at just the right angle and height. Such pulling cutsdown on the resistance, resulting in a much faster and better job.Construction of these pull towers allows the use of much larger andlonger actuating cylinders, that do not have to be handled by hand.

SUBSECTION A shows the tie-down at front of car. SUBSECTION B shows thetie-down further back on car. SUBSECTION C shows the tie-down forpulling from the pull towers. While pull tower movement is stretchingframe, auxiliary jack 44 applies pressure upwardly to the frame.

The series of cross-members in each rail 9 provides a ready place fortie-downs at any angle or point on the rails 9. regardless of angledesired. as shown in SUB- SECTIONS A. B, & C. Also there is no problemfinding a spot to set jacks 45 on rail assembly 9, for pushing up onbody or frame or both, as shown in SUBSECTION D.

The entire machine is mounted on a pedestal 3, hinged from the floor andsecured by lag-screws. The pedestal 3 is also an axis for the pulltowers 5, permitting the towers 5 to be positioned for pulls from anydesired angle. The hydraulic pump 55 is mounted inside the pedestal 3,for both protection and convenience. Pump 55 is activated by remotecontrol 49. Pump 55 is easily removable from pedestal 3 for servicing.

In FIG. 2, the apparatus or machine, is shown lowered at one endcompletely tilting it to receive a vehicle, not shown without usingremovable ramps. In order to lower it, a safety stand 69 must first bepulled and pivoted from its upright position which is automaticallytaken when the apparatus is tilted back up to its hori zontal position.In such elevated horizontal position. any vehicle raised by theapparatus is sufficiently high so no pit volume in the building isneeded below the vehicle being repaired.

In FIG. 3. the apparatus or machine, is shown in a top view toillustrate the almost unlimited number or tiedown or anchoring locationsavailable along rail assemblies 9. Also indicated are the multipleradial positions of the pull towers 5. As shown. the towers 5 areapplying power in three different directions at one time. Also. theauxiliary jack 45 is pushing on a short link in the frame ofthe vehicleforcing it to bend in the desired location or spot. There is no losttime or heavy lifting in making hookups, since the pull towers 5 stayrigged for action at all times. The auxiliary cylinder 45 is a standardl0-ton body jack, hooked into the hydraulic system on the machine to beused as shown in SUB- SECTION D and FIG. 3.

Rail assemblies 9 consists or a seies of single beams 10 on edge, weldedto a series of cross-members 11. The two rail assemblies are mounted ontwo main crossmembers 15 which are welded to the pedestal 3, and theyare also mounted on one cross-member 16 at the rear of the machine. Thelift device is also fastened to the rear cross-member 16. The advantageof fabricating the rail assemblies 9 in this manner is the cre ation ofspaces between the beams and regular spacings of cross-members 11,making it a very simple operation to tie any vehicle to a rail assembly9, regardless of angle or location required by each repair job.

Throughout the utilization of all apparatus of the various embodments,special body clamps are provided and often used. Sone cars do not haveframes and it is very difficult at times to find a place suitable fortying the car down, in order to pull as hard as necessary at times,without causing damage to an undamaged part of the car. However, usuallyon a unitized body, there is a small flange on the lower part of thebody sill, that is a suitable tie-down location, provided you haveclamps capable of holding on to this small flange. These clamps of FIGS.3A, 3B, and 3C are designed for this purpose and they are very simple touse. The clamp, placed in position. bolt 152 and nut 153 are tightenedsnugly to hold clamp unitl pressure is applied. The chain is hooked inthe space provided in part and, as pressure is applied, part 150 slipsback on parts 151, sinking teeth into the body flange. The harder thepull. the tighter the squeeze. It will not slip.

In FIGS. 4 and 4C, portions are broken away to indicate construction ofpull tower asemblies 5, pedestal assemblies 3, the hydraulic systemleading to and departing from hydraulic pump 55, and the lokcing devices13/1] 1 to keep pull towers 5 in their respective selected radialpositions. There are two pull tower lock systems shown. The pin system111, is the most desirable of the two. The hydraulic cylinder 57, etc,.is tucked inside the pull tower poles 113. This enables the use oflarge, long cylinders and leaves the hookup ready to use at all timeswithout any handling of jacks, heavy attachments, etc. The only settingup required is to adjust the height of pull and angle. merely by settingidler assembly 101 to the desired spot on the pull tower pole 113. Thispull tower pole may be attached to many other types of frame machinesnot shown improving them considerably and it may be mounted in the floorof a shop to provide a ready pull facility when needed on minor bodyrepair jobs.

In FIGS. 4 and 4A and in all embodiments, an idler assembly 101 for eachpull tower 113 is adjustable to any desired height and angle. Set screw124 holds idler assembly 101 at the desired location until pressure fromcylinder 57 is appliedv As chain 102 is pulled. a resulting upward forceon one side of idler assembly 101 creates a binding action between itand tower pole 113. The harder the pull. the tighter this gripping orbinding action becomes thereby holding idler assembly 10] at the properheight and angle throughout the entire pulling operation utilized topull out damaged portions of a vehicle.

In FIGS. 4 and 4B, the hyraulic system is illustrated. After a vehicleis in place, the lift assembly shown in FIG. 5, is raised to thatposition as a valve type 41 lo cated adjacent to it is opened. After theapparatus or machine is leveled, this valve is closed. Thereafter, othervalves 41 controlling fluid flow to other cylinders are selectivelyopened and closed to cause movement under pressure while adjustments aremade to others. One or more hydraulic cylinders may be regulated whilekeeping pressure on all thoses that previously received hydraulic liquidunder pressure. A central pump 55, driven by an electrical motor or acompressed air motor, selectively supplies hydraulic fluid underpressure through these various valves 41 to actuators 44, 45 and thoseactuators referred to as pull tower cylinders 57.

Although a hydraulic system is shown and described, compressed airactuators and mechanical actuators may also be used.

in regard to this embodiment presented in FIGS. 1 through 5, thefollowing numerals identify the following parts in reference to thespecific groupings indicated:

Hydraulic Components and Related Components Hydraulic hose to pulltowers; 41 Control Valves; 42 Bracket fastens control valve to machine;42 Clips to secure hydraulic hose; 44 hydraulic cylinder, operating liftapparatus; 45 auxiliary jack, coupled into the hydraulic system; 46Nipple (body jack); 47 attachments (body jack); 48 Remote control line;49 remote control switch; 50 Body jack attachments; 51 Hydraulic hose tolift cylinder; 52 Hydraulic hose to auxialiary body jack; 53 Hydraulicline junction box; 54 hydraulic hose to pump assembly; 55 Hydraulic pump(air driven or electric); 56 Plate supporting pump assembly and junctionbox; and 57 pull tower cylinder.

Lift and Stand Assembly 1 60 Bracket holding Hydraulic Cylinder 44; 61Pins; 62 Brackets; 63 Upper arms; 64 Lower arms; 65 Shaft (cylinderpushes on this shaft to raise machine); 66 Mounting bracket (fastened tofloor); 67 Mounting bracket leg screws (fastens lift assembly to floor);68 Bracket; 69 Leg stand; 70 Jam nut; 71 Leg Bolt; 72 Shaft; 73 Stop;and 74 Brace;

Tie-Down Attachments Tiedown or pull hook with chain hook slot for fastchain adjustment; 8] Tie-down chain; 83 Tie-down or pull hook; 83Tie-down or pull hook; 84 Pull plates; 85 Shackles with chain hook slots(for fast adjustments) 86 Bolts (usually bumper bolts); 87 Chain hooks.

Pull Tower Assembly 5 101 ldler assembly; 102 Pull chains; 103 Upperpush rod cap with chain hook slot for chain adjustments; 104 Guideflange for holding pull chain in center of Push rod; 105 push rod(Movable up and down and will turn 360 106 weld on pull plate; 107 Pullchain hook; 108 Holes for bolts or pins (for hooking pull towers intoposition) 109 Sleeve (used with pins 111); 110 Nut (if bolts 13 areused); 111 Pin for securing pull tower; 112 Spacer flange secured to pin111; 113 pull tower pole; 114 Upper part of pull tower pole brace; 115Gussets (pull tower pole Brace) 116 Bar (welded inside of pull towerpole 113); 117 Flange (secured to cylinder 57 to keep cylindercentered); 118 Lower push rod cap; 119 Upper part of pull tower beam;120 Lower part of pull tower beam; 121 Inner brace (pull tower beamwelded to 119420-122 and 122 End plate (Pull tower beam).

Idler Assembly 101 123 Collar; 124 Thumb set screw; 125 Pin; 126Bracket; 127 ldler pulley; and 128 Brace.

Rail Assembly 9 10 Beams in main rails; 11 Cross-members in rails; 12End cross members; 13 Anchor bolts or pins to secure pull tower torails; 14 Plate or washers under bolts 13; 15 Main cross members,supporting rails, welded to pedestal; 16 Rear cross member, supportingrail assembly lift device; 17 upper section of cross member 16; and 18Movable cross member, (Movable between rails).

Pedestal Assembly 3 20 Pedestal; 21 Bracket; 22 Collar; 23 Flangecollar, welded to Pedestal 20; 24 Mounting bracket; 25 Mounting Shaft,welded to Pedestal 20 and Flange 23; and 26 Door (Pump assembly liftsout through this door for service).

Body Clamps Clamp housing can be fabricated or forged; 151 Wedges withteeth attached; 152 Bolt; and 153 Nut.

Car Body B Car Frame F Other Embodiments Based on Pedestal RadiallyAdjusted Elongatable Towers of FIGS. 1 through 5.

Although FIGS. 1 and 2 shown one central pedestal 20, two pedestals oneon each side of a vehicle location may be used. Also one pedestal at thefront and one at the back of each vehicle location may be used. Sucharrangements are dependent on the requirement for even greaterconvenience in effecting repairs. Where more pedestals are to be usedgenerally additional facilities such as pits or ramps are included inthe overall build- Embodiments Shown in FIGS. 6 through 12, ElongatableTowers Radially Adjusted About A Pivot Pin Mounting Secured to Either aFixed Position Hold Down Ramp or a Movable Hold Down Ramp and UsedTogether As first observed in FIG. 6, as assembly is prefer ablyinstalled in the center of a bay of a body shop and secured to the floorprovide an embodiment of the invention at a lower cost but retainingmany of the features. 1f damage is on left side of car, the car isdriven on assembly 175 as shown in FIG. 6. 1f damage is on the rightside of car, the right side of the car is placed on the assembly 175.The pull tower on assembly 175 is movable as indicated, allowing pullsfrom several angles. There are unlimited tie-down spaces on railassembly. Regardless of the shape of a frame or body, there is atie-down space in the rail that will line up, to pull straight on thecar or frame or in any angle desired. By tying a car to the rails in thedesired spots and thereafter operating the pull towers and theirhydraulic systems repairs are commenced.

When assembly 200 is used with assembly 175, you have a very versatileframe and body alignment machine, enabling pulls from any point aroundthe vehicle at heights desired. Assembly 200 is movable along assembly175 as indicated in FIG. 6. Also. assembly 200 is used on the oppositeside of assembly 175, as shown in FIG. 8. By using assemblies 175 and200 it is possible to pull at any point completely around the vehicle.In FIG. 7 asembly 200 is being used as a portable apparatus or machine.movable to any other stall or location desired. The pull tower onassembly 200 is also movable. as indicated. making it possible to pullat several angles without resetting the machine. When using unit 200 asa portable, the weight of the car is placed directly on the machine torest firmly on blocks 203 that are then directly on the floor.

There are many advantages gained in using this portable unit 200. suchas the operation of movable pull tower, the wide variety of tie-downspaces available. and the way the weight of the car is directly on themachine. holding it much more firmly in place throughout the pullingoperation. Also. a detachable or sliding extension can be added to therail assembly, if desired. In FIG. 8. the assembly 200 is being used onopposite side of assembly 175. In FIG. 9, unit 200 is rolled underassembly 175 using the caster assembly. In FIG. 10, portions are cutaway to view the construction of the pull tower beams. which arefabricated to fit on both sides of rail 9. to prevent any twist whenmaking angle pulls.

In FIG. II. a front-end alignment machine is indicated in part toillustrate how one or more portable assemblies or units 200 are used tocreate a better frontend aligment machine. It is also then a very goodframe and body alignment machine. and also often a very fine portableframe machine. For shops growing in business and capital. the machineand/or apparatus shown in FIG. 11 may be purchased, for example. inthree orders over a reasonable period of time. As additional portableassemblies or units 200 are purchased. they are also conveniently rolledunder portions of a front-end machine. as illustrated in FIG. 12.

Embodiment Shown in FIG. 13. Pull Towers Secured to Shop Floors andYards On many occasions it is very desirable to have a ready pull towerfor quick. easy pulls to align fender. hoods. bumpers. inner panels andframe horns. that normally would be too small to place on a frame rackor go to a lot of trouble rigging up a portable machine or body jacks.For maximum efficiency for these small alignment jobs, pull towers. asshown in FIG. 13, are mounted in the floor in strategic positins in eachstall. When used with some well secured floor anchor plates. it ispossible to align major body and frame alignment jobs with these pulltowers. When sleeves 226 are embedded in shop floor. pull tower assemblycan be moved from one location to another. Also. these pull towers couldbe positioned in the yards of shops.

Embodiments Shown in FIGS. 14 and 15, Pull Towers Movably Secured toRails. Etc.

Where a high volume of severely damaged vehicles are being repaired. theembodiments shown in FIGS. l4 and 15 are used. Pull towers are movedabout on guiding rails that encircle the working bay area. A pit may andmay not be used. Where pull towers are high. tension members. such aschains. are guided over their tops through idlcrs 258 and down again forsecuring in chain slots on collars 262. These collars 262 bind on post I13 n hcn hydraulic pressure created forces cause upward tower motements.

Additional Parts Used in Assemblies and 200 176 Bracket, securingassembly 175 to floor. two required; 201 Pin. securing pull towerassembly to rail assembly; 202 Caster assembly; 203 Blocks. to supportmachine when Casters are compressed; 204 Stop, adjustable along top sideof rail assembly. not needed except when Unit 175 and 200 are usedtogether; 205 any suitable pump assembly; 206 Pin. securing upper andlower rail assemblies when used together; 207 Caster Bracket; 208 Casterspring; 209 Caster spring housing; 210 Stop or washer; 211 Caster Wheeland Fork Assembly; 212 Bushing; 215 Upper plate; pull tower beam; 216Gusset; 217 Center plate. pull tower beam; 218 Lower plate, pull towerbeam; 220 Front-end alignment turn tables; 221 Bracket assemblysupporting machine; 225 Flange or stop; 226 Sleeve embedded in floor;250 Structural frame assembly; 251 Lower Support Bar; 252 Rail supportassembly; 253 Upper and Lower track asseblies; 254 Upper roller; 225Upper roller pin; 256 Upper pull tower bracket; 257 Push rod Idlerbracket; 258 Push rod idler; 259 Lock pin spring; 260 Lock pin; 261 Lockpin pull rope; 262 Pull chain adjustment collar; 263 Anchor Brackets;264 Lower rollers; 265 Lower pull tower bracket; 266 Lower lock pin; and267 Lower roller bushing.

SUMMARY OF ADVANTAGES The apparatus selected in one or more of itsembodi ments performs the versatile function of pulling damaged parts indirections reversed from those causing such damage. The metals, withoutheating. are pulled back to their originally specified relativelocations or at least within the original factory designated tolerances.Depending on the volume and nature of jobs to be undertaken in a shop.the apparatus may be increased in size, function and capacity with addedcomponents being adaptable with no change or minor changes to previouslyacquired apparatus.

Throughout all components, the utilization of the pulling towers andtheir conveniently arranged selective positioning and hold-downaccessories, results in quick and accurate setups requiring no liftingnor awkward stances or manipulations on the part of anyone in a shop whois repairing a vehicle.

DESCRIPTION OF ADDITIONAL EMBODIMENTS FIG. 16 illustrates in plan viewan improved embodiment of the treadways of the platform system of FIG.3. It is comprised of a plurality of longitudinal elements 322A. 3228.322C 322N. These are attached in side-by-side parallel arrangements soas to provide a top and a bottom surface member. both of which are planeand parallel to each other. with a corresponding plurality of verticalsupports or ribs. supporting the spaced apart surface members. There area plurality of openings 326A, 326B. 326C 326N in a twodimensional arrayof positions. These generally comprise rectangular openings in the topsurface member and the bottom surface member. whereby the pairs ofopenings are in alignment along an axis perpendicular to the surface ofthe treadway. While rectangular openings have been illustrated. it willbe clear that circular openings can equally well be used. The purpose ofthese openings will be explained more fully in relation to FIG. 22A.

The principle improvement of this invention lies in the use of a plane.rigid platform. composed of two treadways upon which a vehicle can beplaced in order to be operated on by the force-application apparatus ofthis invention. The important part is that all forces applied to theobject (or vehicle) are applied between the vehicle and the platformsystem. The system is de signed to be sufficiently rigid so that noother anchoring means for forces applied to the vehicle are required.The treadways are designed not only to support the vehicle but also toprovide a plurality of openings by means of which hooks, fixtures. rods.etc.. can be quickly inserted into or removed from any one of theplurality of openings to provide anchoring means through which forcescan be applied between the vehicle and the treadways. Although variousmeans of applying forces, such as hydraulic rams, etc., can be used, animportant part of this invention encompasses the use of the verticalpull towers which are attached to the platform system by means of armswhich are pivotally connected to the system, so that the tower can beswung into various positions and locked therin so that the direction ofapplication of the pulling force of the tower can be adjusted asdesired.

The essential feature of the treadways is that they be plane and rigidand have a multitude of openings. the axis of which are perpendicular tothe plane of the treadway. The construction can be one of many. Forexample, FIG. 17 illustrates one way in which the treadway can beconstructed. It shows a cross section across one treadway taken alongthe line 17-17 of FIG. 16. There are a plurality ofI beams 322A, 3228.322N which are placed in longitudinal parallel contiguous positions andare welded along their touching edges 324 to provide a rigid slabconstruction which comprises an upper surface 323 and a lower surface325 which are both plane and parallel to each other and spaced apart bythe width of the central ribs of the I beams. Either before or after theI beams are welded to form the treadway, rectangular openings 326A,3268, 326C 326N are cut into the flanges of the l beams. one-half out ofeach of the adjacent flanges. As shown in FIG. 16. when the l beams arewelded together along the edges 324 the line of the edges will be acenter line for the opening 326.

The use ofthe I beams to provide not only the stiffening ribs but alsothe top and bottom surfaces, which form the treadway as shown in FIG.17, is a preferred embodiment. However, it is possible also as shown inFIGS. l8, I9, 20. and 2] to construct a rigid treadway by other means.

Referring now to FIG. [8 the treadway can be constructed by usingseparate steel plates 332 and 334 which are spaced apart and attached tolongitudinal vertical metal strips 330 such as by welds 336 and 338.Prior to assembly. the openings 326 are cut into the two plates 332 and334, such as. for example. by superimposing the two plates and by meansof a torch burning through the two plates to form rectanular openings326. Of course. these openings can he rectangular or circular. Also theycan be punched through the plates as is well known in the art. Thevertical spacing-ribs 330 are then welded to the bottom plate such as336. The assembly is then turned over on top of a top plate and the ribs330 are then welded to the plate 334 producing welds such as 38. In thiscase the welding rod can be ap lied through the openings 326 to appplythe welds between the vertical strips and the plates 334.

FIG. I9 represents another embodiment of the construction of thetreadway of FIG. 16. This utilizes a plurality of rectangular tubes 365placed in a longitudinal, parallel. contiguous relation with twochannels 366 one on either side, all welded together along the corners324. This construction not only provides the top and bottom surfaces butalso provides a large number of perpendicular ribs to provide thestiffening required. In this case, the openings 326 are cut through thetop and bottom surfaces of the rectangular channels.

FIG. 20 illustrates still another construction in which a plurality ofsteel channel sections 368 are placed parallel to each other and spacedapart. Short rectangular blocks 370 are placed between the flanges ofthe channels 368 and the two end channels 336 so as to provide openings326A. 326B, 326N between the flanges of the channels for a selectedlength. The small blocks 370 are welded to the flanges of the channelsalong the edges 374, as indicated.

FIG. 21 shows still another embodiment of the construction of thetreadway of FIG. 16. This uses a top and bottom plate (only the bottomof which, 332 is shown). Two angle sections 366 are used as in FIGS. 19and 20. Openings 326 are cut into the bottom plate 332 as in FIG. 18 andshort lengths of tubing 376 are placed over all or part of the openings326, and are welded to the plate 332 as in FIG. 18. The internaldimensions of the rectanular tubing is somewhat larger than the size ofthe openings 326 so that a hook or other device can be inserted into theopening and have a lip against which it can pull. without interferingwith the tubing section welded around the opening. After the portions oftubing 376 are welded to the plate 332 as are the longitudinal channelsections 366, the top plate is placed over the assembly and the openings326 which have previously been prepared in the top plate are lined upvertically with the openings 326 in the bottom plate and the assembly isclamped together, turned over, and the top plate is then welded to thesecond ends of the tubing sections.

It will be clear that there are a number of ways in which a rigid planetreadway system can be designed and constructed. It is important thatwhichever way is used that there be sufficient rigidity so that themaximum forces which will be applied to the treadway will not cause itto buckle or bend. Furthermore, the plurality of openings in the top andbottom surfaces are utilized in several different ways for theapplication of forces. In one way chains can be linked down one openingand up adjacent opening to provide a strong anchor to the treadway. Inother ways the chains or cables can be attached to hooks which areinserted into the openings and a third and important way in which theopenings can be utilized for anchoring purposes is illustrated in FIGS.22A, and 228.

As shown in FIG. 22A. a post which may be a solid rectangularconstruction or a rectangular tubular construction of appropriatedimensions. so as to freely be inserted into the plurality of openings326 in the treadway can be used to apply compression or tension forcesto the vehicle or object to be worked on.

These posts 352 are inserted through the two openings in the top andbottom surfaces of the treadway and are held in any desired verticalposition by means of a locking clip 356. This is illustrated or in moredetail in FIGS. 23A and 238. It comprises a rectangular opening 350 in astrip 356. which is slightly larger than the size of the post 352 so itcan easily slip up and down on the post. It has a short leg 360 bentsubstantially at right angles. so that when the past is in the properposition and the clip can he slipped over the post and pressed down tillthe leg 360 contacts the top surface. Further movement downward of thepost causes it to bind with the clip and be held in that positionwithout dropping fur ther through the opening. The rectangular tubularpost 352 can be made long enough so that it can reach upwardly to pressagainst a bar frame. axel. or other portion of the frame of the vehicle.It is possible also to make one edge 354 of the rectangular tube extendupward beyond the top of the tubing 352 so that it can reach up intonarrow gaps between portions of the ve hicle to apply the force that isrequired. Alternatively, bars of various cross sections can be insertedinto the tubing 352 to extend them to greater heights so that they maypress directly against the vehicle or serve to anchor a chain so that apull can be made against the bar 352. and from the bar to the treadway.

It will be clear that by the use of the rigid platform system of thisinvention the two or more opposing forces which are to be applied to theobject or vehicle on the platform are both anchored to portions of theplatform system. These may be inherent portions such as the openingsthrough the treadways. They may be other portions of the platformsystem. such the vertical pull towers which are attached in a pivotalmanner. They may be still other structure, such as frames to which arepivotally attached vertical pull towers. these frames being removablyattached as desired. to the platform system. One such removablyattachable device is illustrated in FIG. 12. This is a frame supportedon casters which can be maneuvered into position under the platform andbolted thereto. the frame supporting a vertical pull tower. A pullingforce can be applied between the object and the pull tower, which forceis directly connected back from the pull tower, through the movablesubstructure to the platform system. It is clear also that the verticalpull towers which are pivoted to the platform system can be pivotallyattached to a central pedestal 20 of FIG. I, if there is one. or to thetreadways as in FIG. 6. or to cross members as in FIG. 6. or toremovably attachable members as in FIG. 12. The important point is thatduring the pulling operation all forces are anchored directly orindirectly to the platform system. The platform system may includepermanently attached parts. and removably attached parts, which. for thepurpose of pulling are clamped to and are part of the platform system.

While the invention has been described with a certain degree ofparticularity. it is manifest that many changes may be made in thedetails of contruction and the arrangement of components it isunderstood that the invention is not to be limited to the specificembodiments set forth herein by way of exemplifying the invention. butthe invention is to be limited only by the scope of the attached claimor claims. including the full range of equiuilency to which each elementor step thereof is entitled.

What is claimed:

1. Apparatus for applying equal and opposite forces to a mechanicalstructure such as an automotive vehicle body or frame comprising:

a. a platform system;

b. means on said platform system for supporting said structure;

c. at least one vertical pull tower means pivotally connected about avertical axis fixed to said platform system notatably movable to adesired position relative to said structure;

d. means to vertically elongate said tower;

e. means to connect a tension member between said vertically elongatemeans and a first portion of said structure to apply a first force tosaid structure; and

f. means to apply a second force between a second portion of saidstructure and said platform system.

2. The apparatus as in claim 1 in which said platform system includes atleast one treadway on which said structure is supported.

3. The apparatus as in claim 2 in which said treadway comprises a pairof plane, parallel spaced-apart plates. a plurality of spaced elementsbetween. fastened to and supporting said plates, which comprise top andbottom members of said treadway.

4. The apparatus as in claim 3 and including a plurality of pairs ofopenings in said top and bottom member. each pair of openings inalignment perpendicular to the plane of said treadway.

5. The apparatus as in claim 4 including cylindrical rigid beam meansremovably received in said openings.

6. The apparatus as in claim 2 including means to pivotally connect saidpull tower to said treadway.

7. The apparatus as in claim I in which said platform system includes avertical pedestal. and including means to pivotally connect said pulltower to said pedcstal.

8. The apparatus as in claim 1 including means to lock said pull towerto said platform system in said desired position.

9. The apparatus as in claim I in which said platform system meansincludes means to support said at least one treadway substantially in ahorizontal plane.

10. The apparatus as in claim 6 in which said support means includesmeans by which said at least one treadway can be tilted so as to form aramp to receive said structure.

11. The apparatus as in claim 1 in which said structure comprises awheeled vehicle.

12. The apparatus as in claim 1 in which said means to verticallyelongate said tower is hydraulically actu able internally of said tower.

13. The apparatus as claim 1 in which tension member is a chain orcable.

14. The apparatus as in claim I in which said second force comprises atensile force. and said apparatus includes tension menas connectedbetween said second portion and said platform system.

IS. The apparatus as in claim 2 in which said second force comprises acompression force and said apparatus includes rigid means removablyattached to said second portion of said structure to resist its motionunder said first force.

I6. The apparatus as in claim 15 in which said rigid means comprises acylindrical means removably received in any one of a plurality ofvertical openings in said treadway.

I7. The apparatus as in claim [5 including removable locking clip meansto adjust the depth of insertion of said cylindrical means into saidopening.

18. The apparatus as in claim 2 including two treadways supported by aplurality of cross members in coplanar spacedapart parallel relation.

19. The apparatus as in claim 18 including a plurality of pairs ofopenings in said cross members.

20. The apparatus as in claim 1 including independent frame meansremovably attached to said platform system, said pull tower meanspivotally attached to said frame means.

2]. In an apparatus for applying equal and opposite forces to amechanical structure including work plat form and treadway means tosupport said structure, means to apply a plurality of forces between atleast one point on said structure and said platform the improvementwherein each of a pair of treadways com prises:

a. a pair of overlapping plane. parallel spacedapart top and bottomplates;

b. a plurality of spaced elements between, fastened to and supportingsaid plates; and

e. a plurality of pairs of openings in said top and bottom plates ofsaid platform, said pairs of openings in alignment perpendicular to theplane of said platform.

22. The apparatus as in claim 21 in which said spaced elements include aplurality of spaced-apart. parallel, longitudinal members.

23. The apparatus as in claim 22 in which said longi tudinal memberscomprise l beams in parallel spaced relation.

24. The apparatus as in claim 22 in which said longitudinal memberscomprise strips in parallel spaced re lation, the planes of said stripsperpendicular to said plates.

25. The apparatus as in claim 22 in which said longitudinal memberscomprise channels in parallel spaced relation.

26. The apparatus as in claim 22 in which said longitudinal memberscomprise rectanglular tubes in parallel spaced relation.

27. The apparatus as in claim 21 in which said spaced elements compriseshort lengths of cylinders in a twodimensional array of positions overthe area of said platform.

28. The apparatus as in claim 21 including rigid cylindrical beam meansremovably received in said open- 16 ings.

29. The appartus as in claim 28 including removable locking clip meansto adjust the depth of insertion of said beam means in said openings.

30. The apparatus as in claim 28 in which said beam means are tubularand including rod means removably received in the central openingtherein.

31. The apparatus as in claim 21 in which said openings are rectangularin shape.

32. The apparatus as in claim 21 in which said openings are circular inshape.

33. Pull tower apparatus for use in a system for applying forces to amechanical structure such as an automotive vehicle body or frame,comprising:

a. a vertically supported housing means comprising a cylindrical tube;

b. operating means comprising a cylindrical means reciprocably androtatably received in said housing:

c. hydraulic actuator means inside said housing below said operatingmeans, one of a cylinder and piston end of said actuator supported bysaid housing, the other of said cylinder and piston end of said actuatorconnected to the bottom end of said operating means;

d. a pull chain;

c. means connected to said operating means to receive said pull chain;

f. idler pulley means, to receive said chain, attached to a ring meansslidably and rotatably surrounding said housing and including means tolock said ring means to said housing; and

g. means to support said pull tower means in a vertical position.

34. The pull tower apparatus as in claim 33 in which said support meanscomprises vertical socket means in said system into which said housingis slidably received.

35. The pull tower apparatus as in claim 33 in which said support meanscomprises arm means hingedly supported by said system, said towerfastened to said arm means.

36. The pull tower apparatus of claim 33 in which said means connectedto said operating means is an idler pulley and means to secure one endof said chain to said housing means.

1. Apparatus for applying equal and opposite forces to a mechanicalstructure such as an automotive vehicle body or frame comprising: a. aplatform system; b. means on said platform system for supporting saidstructure; c. at least one vertical pull tower means pivotally connectedabout a vertical axis fixed to said platform system notatably movable toa desired position relative to said structure; d. means to verticallyelongate said tower; e. means to connect a tension member between saidvertically elongate means and a first portion of said structure to applya first force to said structure; and f. means to apply a second forcebetween a second portion of said structure and said platform system. 2.The apparatus as in claim 1 in which said platform system includes atleast one treadway on which said structure is supported.
 3. Theapparatus as in claim 2 in which said treadway comprises a pair ofplane, parallel spaced-apart plates, a plurality of spaced elementsbetween, fastened to and supporting said plates, which comprise top andbottom members of said treadway.
 4. The apparatus as in claim 3 andincluding a plurality of pairs of openings in said top and bottommember, each pair of openings in alignment perpendicular to the plane ofsaid treadway.
 5. The apparatus as in claim 4 including cylindricalrigid beam means removably received in said openings.
 6. The apparatusas in claim 2 including means to pivotally connect said pull tower tosaid treadway.
 7. The apparatus as in claim 1 in which said platformsystem includes a vertical pedestal, and including means to pivotallyconnect said pull tower to said pedestal.
 8. The apparatus as in claim 1including means to lock said pull tower to said platform system in saiddesired position.
 9. The apparatus as in claim 1 in which said platformsystem means includes means to support said at least one treadwaysubstantially in a horizontal plane.
 10. The apparatus as in claim 6 inwhich said support means includes means by which said at least onetreadway can be tilted so as to form a ramp to receive said structure.11. The apparatus as in claim 1 in which said structure comprises awheeled vehicle.
 12. The apparatus as in claim 1 in which said means tovertically elongate said tower is hydraulically actuable internally ofsaid tower.
 13. The apparatus as claim 1 in which tension member is achain or cable.
 14. The apparatus as in claim 1 in which said secondforce comprises a tensile force, and said apparatus includes tensionmenas connected between said second portion and said platform system.15. The apparatus as in claim 2 in which said second force comprises acompression force and said apparatus includes rigid means removablyattached to said second portion of said structure to resist its motionunder said first force.
 16. The apparatus as in claim 15 in which saidrigid means comprises a cylindrical means removably received in any oneof a plurality of vertical openings in said treadway.
 17. The apparatusas in claim 15 including removable locking clip means to adjust thedepth of insertion of said cylindrical means into said opening.
 18. Theapparatus as in claim 2 including two treadways supported by a pluralityof cross members in coplanar spacedapart parallel relation.
 19. Theapparatus as in claim 18 including a plurality of pairs of openings insaid cross members.
 20. The apparatus as in claim 1 includingindependent frame means removably attached to said platform system, saidpull tower means pivotally attached to said frame means.
 21. In anapparatus for applying equal and opposite forces to a mechanicalstructure including work platform and treadway means to support saidstructure, means to apply a plurality of forces between at least onepoint on said structure and said platform, the improvement wherein eachof a pair of treadways comprises: a. a pair of overlapping plane,parallel spacedapart top and bottom plates; b. a plurality of spacedelements between, fastened to and supporting said plates; and c. aplurality of pairs of openings in said top and bottom plates of saidplatform, said pairs of openings in alignment perpendicular to the planeof said platform.
 22. The apparatus as in claim 21 in which said spacedelements include a plurality of spaced-apart, parallel, longitudinalmembers.
 23. The apparatus as in claim 22 in which said longitudinalmembers comprise I beams in parallel spaced relation.
 24. The apparatusas in claim 22 in which said longitudinal members comprise strips inparallel spaced relation, the planes of said strips perpendicular tosaid plates.
 25. The apparatus as in claim 22 in which said longitudinalmembers comprise channels in parallel spaced relation.
 26. The apparatusas in claim 22 in which said longitudinal members comprise rectanglulartubes in parallel spaced relation.
 27. The apparatus as in claim 21 inwhich said spaced elements comprise short lengths of cylinders in atwo-dimensional array of positions over the area of said platform. 28.The apparatus as in claim 21 including rigid cylindrical beam meansremovably received in said openings.
 29. The appartus as in claim 28including removable locking clip means to adjust the depth of insertionof said beam means in said openings.
 30. The apparatus as in claim 28 inwhich said beam means are tubular and including rod means removablyreceived in the central opening therein.
 31. The apparatus as in claim21 in which said openings are rectangular in shape.
 32. The apparatus asin claim 21 in which said openings are circular in shape.
 33. Pull towerapparatus for use in a system for applying forces to a mechanicalstructure such as an automotive vehicle body or frame, comprising: a. avertically supported housing means comprising a cylindrical tube; b.operating means comprising a cylindrical means reciprocably androtatably received in said housing; c. hydraulic actuator means insidesaid housing below said operating means, one of a cylinder and pistonend of said actuator supPorted by said housing, the other of saidcylinder and piston end of said actuator connected to the bottom end ofsaid operating means; d. a pull chain; e. means connected to saidoperating means to receive said pull chain; f. idler pulley means, toreceive said chain, attached to a ring means slidably and rotatablysurrounding said housing and including means to lock said ring means tosaid housing; and g. means to support said pull tower means in avertical position.
 34. The pull tower apparatus as in claim 33 in whichsaid support means comprises vertical socket means in said system intowhich said housing is slidably received.
 35. The pull tower apparatus asin claim 33 in which said support means comprises arm means hingedlysupported by said system, said tower fastened to said arm means.
 36. Thepull tower apparatus of claim 33 in which said means connected to saidoperating means is an idler pulley and means to secure one end of saidchain to said housing means.